Interactive exploration of the underwater sonar space

Today, the US Navy's submarine fleet is equipped with a multitude of advanced, highly capable acoustic sensors and systems that are utilized in many aspects of tactical, navigational, and operational command and control (C2). These modern sonar systems collect, process, store, disseminate, and display sensor data. It is the real-time operational understanding of this collective sensor data that we term sensorspace awareness. Rapid advances in processing techniques, computing power, and sensor technology present a new challenge - sonar operators require extensive training and experience in order to deal with an enormous amount of acoustic data using limited 2D display and interaction tools - nearly unchanged in the past 25 years. Fraunhofer CRCG and the Naval Undersea Warfare Center present a highly interactive Large Scale Visualization Environment (LSVE) for performing the essential tasks of detection and classification of sonar contacts. Our prototype application employs a semi-immersive 3D display system, multiple and mixed modalities of interaction and feedback, and state-of-the-art volumetric visualization and abstraction techniques. The described use-case includes simulated passive sonar data from an advanced towed array system, chosen for both the amount and high degree of dimensionality typical of the data produced. In our scenario, an operator uses the LSVE to rapidly detect a contact in a low signal to noise environment and performs the task of classification. This paper describes the application scenario, approach and implementation of the LSVE and concludes with experiences, lessons learned, and future directions from both the interactive large-scale visualization as well as an application point of view.